1. Field of the Invention
The present invention relates to a light source module of a lamp for a vehicle, and more particularly to a light source module which makes up a rear combination lamp.
2. Description of the Related Art
The term “rear combination lamp” for a vehicle represents lamps mounted at the back of a vehicle, for example, including a back up lamp which is turned on when the transmission is shifted to reverse gear, a stop lamp which is turned on when a driver steps down a brake pedal, and a turn signal lamp.
Recently, use of rear combination lamps using a Light Emitting Diode (LED) as a light source, which has longer life span and higher light efficiency than conventional light sources has been on gradual increase. With reference to FIG. 1, a light source module 10 for a conventional rear combination lamp includes an LED light source 11, a Printed Circuit Board (PCB substrate) 12 which controls supply of current to the LED light source 11, a reflecting plate 13 which reflects light emitted from the LED light source 11 toward an outer lens 21, and a light diffusing lens 14 which is installed in front of the reflecting plate 13 to diffuse the light emitted from the LED light source 11.
The conventional light source module 10 has the following problems. First, since the conventional light source module 10 is equipped with the reflecting plate 13 installed in front the LED light source 11, the entire optical system including the LED light source 11 and the outer lens 21 has a large size, leading to low flexibility in design, heavy weight, and increased cost.
Second, since the conventional light source module 10 emits light by converting the light emitted from the LED light source 11 into a simple image such as point, line, and plane, its light is poorly visible. When increasing the number of the LED light sources 11 to improve the poor visibility, the cost greatly increases.
FIGS. 2A to 2C illustrate light-emitted images formed by the conventional light source module 10. FIG. 2A is a point image 31 with multiple dots, FIG. 2B is a line image 32, and FIG. 3 is a plane image 33.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.